Portable fletching jig for installing Mylar® helical fletchings on arrows, intended for use in sport archery.

Abstract

Device intended to install on arrow tubes commonly used in the practice of archery three helical fletchings at 120° intervals, characterized in that it comprises a central housing (3) with an orifice in its center and a cylinder (2) equipped with two cable glands at its ends, fixed on said housing (3), through which the user passes the arrow tube (1) and locks it in the desired position by tightening the nuts of the double cable gland;and three articulated arms (6) fixed to the upper face of the housing (3) at 120° intervals, having two plates – one integrated into the arm (6) and the other (5) fixed to it – separated by a thin gap into which the nib (4) can be inserted and prepared for gluing, and articulated at their lower end around a transverse axis allowing the user to rotate said arms (6) until the nib (4) comes into contact with it and remains glued there by means of the double-sided adhesive previously applied to it. Figure to be published with the abbreviation: Fig. 1;

Description

Title of the invention: Portable fletching jig for installing Mylar® helical fletchings on arrows intended for use in sport archery

[0001] The present invention relates to a mechanical device for attaching, using a double cable gland, to any arrow tube with a diameter between 4 and 9.3 mm, and for gluing, at the desired location on the surface of the arrow tube, three helical Mylar® feathers with a length between 1.5 and 5 inches (3.8 to 12.7 cm) at intervals of 120° and at the same height. Previous technique

[0002] The attachment of helical fletchings (or spiral fletchings) made of bi-oriented APET (known under the trade name Mylar® by the manufacturer DuPont) (hereinafter referred to as the fletchings) is traditionally carried out manually because they are not compatible with the fletching devices for rigid or semi-rigid fletchings available on the market. With the current state of the art, the manual attachment of helical fletchings is done in two steps: first, the user marks on the arrow shaft the locations where the fletchings should be attached, possibly using a marking device (for example, the "Triliner" from the German manufacturer Beiter; or the "SpigaMarker" from the Italian manufacturer Spigarelli); second, the user, after applying a strip of double-sided adhesive tape (generally supplied with the fletchings) to the edge of each fletching, proceeds to attach the fletchings manually.This procedure suffers from a lack of precision (approximate parallelism to the shaft axis, imprecise spacing between fletchings), a relatively long application time, and requires considerable dexterity. The device according to the invention, designed specifically for Mylar® helical fletchings, overcomes all these drawbacks, without requiring prior marking of the arrow shaft and without demanding any particular dexterity from the user. Furthermore, due to its small size and light weight, the device is portable.

[0003] The device according to the invention makes it possible to overcome these drawbacks. The device comprises, according to a first characteristic, a central housing with a hole in the middle (hereafter the housing), on the lower part of which is fixed a cylinder having two cable glands at its ends (hereafter the double cable gland), and, in a second characteristic, three articulated arms mounted on the upper part of the housing at 120° intervals (hereafter the arms or articulated arms). The boom tube, inserted through the central opening of the housing and passing through the double cable gland, can be fixed in the desired position by tightening the nuts of the double cable gland. Tightening the nuts This allows the arrow shaft to be secured to the device and centered on its longitudinal axis. Thirdly, each articulated arm has two parallel plates perpendicular to the arrow shaft. One plate is part of the arm, and the other attaches to the first. They are separated by a narrow gap into which the user can slide the fletching so that the surface of the fletching intended to receive the double-sided adhesive strip remains accessible and aligned with the longitudinal edge of the arm. At this point, after applying the double-sided adhesive (usually supplied with this type of fletching), the user will rotate each of the three arms, one after the other, around the joint at their base, until the edge of the fletching with the adhesive makes contact with the arrow shaft.The fletchings will attach to the shaft and remain stuck to the arrow tube when the user moves the arms away from it by rotating them in the opposite direction. This device therefore saves time and improves accuracy compared to manual fletching, and makes mounting Mylar® helical fletchings accessible to everyone.

[0004] The device can be made in different versions depending on the size of the fletchings to be fitted and the diameter of the arrows. Indeed, carbon arrows usually have a diameter between 4 and 6 mm and are generally fitted with fletchings between 1.5 and 3 inches long. Aluminum arrows usually have a diameter between 6 and 9.3 mm and are generally fitted with fletchings between 2.8 and 5 inches long. Thus, the diameter of the openings in the central housing and the double cable gland, as well as the length of the double plate of the three articulated arms, must be compatible with the diameter of the arrows to be processed and the length of the fletchings to be fitted, respectively. The double cable gland can be made in different lengths, provided that the distance between the nuts at its ends is at least 2cm to ensure proper alignment of the boom with the device once the nuts are tightened. The device can be made for right-handed or left-handed nibs. The device shown in the attached drawings is the version for right-handed nibs. For the left-handed version, the only difference will be that the double plate of the articulated arms, designed to hold the nibs, will be located on the opposite side relative to the longitudinal axis of the arm. Brief description of the drawings

[0005] [Fig.1] represents the overall view of the device of the invention, with the arrow tube and the fletchings.

[0006] [Fig.2] represents the lower view of the device, including the double press- tow and the central housing in exploded view.

[0007] [Fig.3] represents the top view of the device with one of the three arm support elements, as well as one of the articulated arms in exploded view. Detailed description

[0008] With reference to these drawings, the housing (3) of the device is provided, in its lower face, with a hollow area intended to receive, by embedding or gluing, the upper nut of the double cable gland (2). The upper face of the housing (3) has an opening (7) in its center aligned with the vertical axis of the double cable gland (2). The opening (7) and the double cable gland (2) are designed to be traversed by the boom tube (1). The boom tube (1), inserted through the double cable gland (2) and the housing (3), is held in position by tightening the two nuts of the double cable gland (2). Tightening the two nuts of the double cable gland (2) will also have the effect of aligning the axis of the boom tube (1) with the axis of the double cable gland (2) and thus with the axis of the device. The cavities (8) present on the upper face of the housing (3) and on the base of the screwable retaining elements (9) serve to accommodate the lower part of the arm (6), including its pivot (10), allowing the arm (6) to pivot around the pivot (10) until it is positioned vertically against the boom tube (1).The elongated shape of the cavities (8) allows the user to place the axis (10) at a distance from the boom tube (1) such that the arm (6) in the vertical position is in contact along its entire length with the boom tube (1) regardless of the diameter of the latter provided that it is between 4 and 9.3mm. The upper part of the arms (6) has a plate facing the arrow shaft, onto which a second plate (5) is mounted parallel to it. The arm plate (6) and the plate (5) are separated by a narrow gap into which a helical fletching (4) can be inserted. The spiral shape of the helical fletchings and the elasticity of the material used to make them allow the user to flatten the fletching to insert it into the gap. Only the area of ​​the fletching (4) intended to receive the strip of double-sided adhesive tape for attaching it will remain accessible once the fletching (4) is inserted into the gap. Once the fletching (4) is positioned in the gap, the articulated arm (6) pivots until the fletching (4) is in contact with the arrow shaft (1).The lower part of the articulated arms (6) has sufficient elasticity to allow the user to slightly flex the arm so that its upper part, containing the feather (4), can be aligned parallel to the axis of the arrow tube when the latter is between 4 and 9.3 mm. The feather (4) attaches to the arrow tube (1) by means of its double-sided adhesive and remains in place by protruding from the gap when the user moves the arms (6) apart by rotating them in opposite directions. The pivots (11) located at the ends of the plate (5) help to align the arm (6) with the arrow tube (1) when gluing the fletching (4). The visual guides (12) allow the three fletchings to be placed at the same height. As a non-limiting example, the device will have a total height – with the arms (6) in the vertical position – between 15cm and 20cm, depending on the length of the arms (6), which in turn will depend on the length of the feathers (4) to be glued, as well as the length of the double stuffing box (2). The width and depth of the device, again with the arms (6) in the vertical position, will be 4cm.

Claims

1.

2. Demands Device for installing on arrow shafts commonly used in archery three helical fletchings at 120° intervals, comprising a central housing (3) with an orifice in its center and a double cable gland (2), i.e. a cylinder with two cable glands at its ends, one end of which is fixed on the housing (3) so that the axis of the housing (3) and the axis of the double cable gland (2) coincide and three articulated arms (6) fixed on the upper face of the housing (3) at 120° intervals, characterized in turn in that they comprise two plates separated by a thin gap into which the fletching (4) can be inserted and prepared for gluing, as well as an articulation located at the lower end of the arm, around a transverse axis (10).The device is characterized in that the user, after passing the arrow tube (1) through the opening of the housing (3) and through the double cable gland (2), locks it in the desired position by tightening the nuts of the double cable gland (2), which has the effect of aligning the axis of the arrow tube (1) with the axis of the housing (3) and the double cable gland (2), and then rotates the arms (6) towards the arrow tube (1) until the feather (4) comes into contact with the latter and remains stuck to it thanks to the double-sided adhesive previously applied to it. The device according to the preceding claim, characterized in that each of the three articulated arms (6) is provided with a plate whose plane is oriented facing the arrow tube, and parallel to this plate is fixed a second plate (5) separated from the first by a thin gap whose shape and thickness are such that a helical feather of length between 1.5 and 5 inches can be slid into it and held in place thanks to its helical shape and the elasticity of its material; that the edge of the feather (4) aligned with the longitudinal edge of the arm (6) which receives the strip of double-sided adhesive tape for gluing remains accessible once the feather (4) has been slid into the gap between said plates; and that once the feather has been glued to the arrow tube, it remains glued to the arrow tube and comes out of said gap when the user moves the articulated arm (6) away from the arrow tube.

3. Device according to claim 1 or claim 2 characterized in that the lower part of the articulated arms (6) has sufficient elasticity to allow the user to slightly flex the arm so that its upper part containing the feather (4) can be aligned parallel to the axis of the arrow tube when the latter is between 4 and 9.3mm.

4. A device according to any one of the preceding claims, characterized in that the cavities (8) receiving the transverse axis (10) of the articulated arms (6) have an elongated shape allowing the user to place the axis (10) at a distance from the boom tube (1) such that the arm (6) in the vertical position is in contact along its entire length with the boom tube (1), regardless of the diameter of the latter, provided that it is between 4 and 9.3 mm.

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